Code P0420 Emissions system

Tiny
COUNTRYGIRL20053
  • MEMBER
  • 2016 CHEVROLET SONIC
  • 1.4L
  • 4 CYL
  • 4WD
  • AUTOMATIC
  • 90,000 MILES
We have replaced the fuel cap and have changed one purge value and after a couple of days the check engine light came back on. So, we put another purge value on it, and it didn't come back on in over a week, and this morning I used auto start and it came right on after I got in the car. Would there be a reason why it could be doing this or is there another reason why?
Monday, November 29th, 2021 AT 11:28 AM

1 Reply

Tiny
JACOBANDNICKOLAS
  • MECHANIC
  • 110,182 POSTS
Hi,

The code, P0420, is related to a catalytic converter not operating properly. Is this the only code you have? I ask because it could be related to the heated oxygen sensor as well. However, if there is no code for the sensor, chances are the converter needs replaced.

Take a look at the pic below. It provides a basic inspection of the converter. Check through it and perform any of the steps you can and let me know the results.

Take care,

Joe

See pic below.
Image (Click to make bigger)
Thumb
Was this
answer
helpful?
Yes
No
Monday, November 29th, 2021 AT 6:35 PM

Please login or register to post a reply.